1991 Johnson/Evinrude Models "EI" 40 thru 55 Service Manual, Page 125Get this manual
Function TestsS.L.OWThis ignition system incorporates the S.L.OWTM warning system which will gradually limit engine speed to approximately 2000 RPM when engine temperature exceeds 203 (95 C)To resume normal operation after the S.L.OWTM warning system has been activated, the engine must cool to 1620 (72 C) and the engine must be slowed to an idleThe S.L.OW TM warning system depends on input from the temperature switch tan leadOn remote electric start models, the S.L.OW TM warning system is isolated from other warning horn signals by blocking diode in the engine wiring harnessTemperature Switch
1Disconnect temperature switch tan lead2Install correct test propellerStart engine in test tank and run at 3500 RPM3Attach engine harness tan lead to clean engine ground If engine slows to approximately 2000 RPM, test temperature switchRefer to Temperature Switch Test, Section